Advance and Immediate Request Admission: A Preemptable Service Definition for Bandwidth Brokers

Differentiated Services Architecture lacks control level functionalities and Bandwidth Brokers are proposed to fill that gap. In order to provide proper control level functionalities, Bandwidth Brokers need to provide services for both advance requests and immediate requests. There is a tradeoff between preemption of immediate flows and utilization of links. It is important for a resource manager to provide the promised QoS level to a flow without any preemption. In this study, we solve the preemption and the experienced QoS problem by defining a preemptable service and explain how this service works and also show the performance and scalability characteristics of resource manager with the addition of a preemptable service.